I convert many books (epub to KindlePreviewer) to mobi format... but I'm having just one pesky problem... Chapter Headings... everything else is wonderful. When I tweak the epub (in Sigil) to show my Chapter Headings in the correct size (just a skosh bigger than the 100% body text), they look fabulous on the Previewer for all Kindle devices (of course not the iPad and iPhone)... however when I get them to my KindleFire to preview on an actual device, the 'skosh' bigger than 100% bodytext (or Normal) has suddenly gotten to be about 115% and bold. Why would this be? Is Kindle Previewer being accurate in its preview? It's a small thing, but I'm a perfectionist and my clients expect that from me!

I convert many books (epub to KindlePreviewer) to mobi format... but I'm having just one pesky problem... Chapter Headings... everything else is wonderful. When I tweak the epub (in Sigil) to show my Chapter Headings in the correct size (just a skosh bigger than the 100% body text), they look fabulous on the Previewer for all Kindle devices (of course not the iPad and iPhone)... however when I get them to my KindleFire to preview on an actual device, the 'skosh' bigger than 100% bodytext (or Normal) has suddenly gotten to be about 115% and bold. Why would this be? Is Kindle Previewer being accurate in its preview? It's a small thing, but I'm a perfectionist and my clients expect that from me!

Oh, and I'm emailing the mobi file to my Amazon acct, where it downloads into my "Doc" heading on the KindleFire. I thought this might have been a problem, but yesterday I purchased one of my client's recent books and the Chapter Heading had the same issue.

Oh, and I'm emailing the mobi file to my Amazon acct, where it downloads into my "Doc" heading on the KindleFire. I thought this might have been a problem, but yesterday I purchased one of my client's recent books and the Chapter Heading had the same issue.

Thirsty:

For what it's worth, that means you're getting k7 conversion, not K8, short-handing it. The "mailto" email addies use the old MBPCreator-style conversion, so you're not getting a MasterMobi, as you would if you converted this through Previewer or Kindlegen. It is important to note that this will also affect a file that has already been made with Kindlegen, prior to being processed through KDP.

So, to be clear: even if you made a K8 book (using CSS, in other words) through KindleGen, if you email the resulting mobi to your Fire device, you will get what is a "down-converted" book. That's why you're having problems, and it's why I asked how you were sending them to your device. To see how the book will really function, you either must sideload the book via real wifi (not emailed "wifi") or USB, or, you must run it through KDP, and then download the sample file, and send that to your Kindle Fire via email. OK?